title: Riboswitches in unexpected places--a synthetic riboswitch in a protein coding region.
abstract: In natural and engineered systems, cis-RNA regulatory elements such as riboswitches are typically found within untranslated regions rather than within the protein coding sequences of genes. However, RNA sequences with important regulatory roles can exist within translated regions. Here, we present a synthetic riboswitch that is encoded within the translated region of a gene and represses Escherichia coli gene expression greater than 25-fold in the presence of a small-molecule ligand. The ability to encode riboswitches within translated regions as well as untranslated regions provides additional opportunities for creating new genetic control elements. Furthermore, evidence that a riboswitch can function in the translated region of a gene suggests that future efforts to identify natural riboswitches should consider this possibility.
authors.affiliation: Department of Chemistry and the Center for Fundamental and Applied Molecular Evolution, Emory University, Atlanta, Georgia 30322, USA.
authors.forename: Shana
authors.initials: S
authors.lastname: Topp
authors.forename: Justin P
authors.initials: JP
authors.lastname: Gallivan
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry* / Q000378:metabolism; D001483:Base Sequence; D003062:Codon / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D009154:Mutation; D016366:Open Reading Frames; D012329:RNA, Bacterial / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D038621:Regulatory Sequences, Ribonucleic Acid; D013806:Theophylline / Q000494:pharmacology
chemical_list: D052157:Aptamers, Nucleotide; D003062:Codon; D012329:RNA, Bacterial; D038621:Regulatory Sequences, Ribonucleic Acid; D013806:Theophylline